1. Field of the Invention
This invention relates generally to a method and apparatus for use in repairing soft tissue, and more particularly, to a method and apparatus for repairing a torn meniscus during arthroscopic surgery.
2. Discussion of the Related Art
There are many techniques employed to repair damaged soft tissue. These techniques include suturing, stapling, taping and the like. Selection of which technique to employ depends upon the type of soft tissue being repaired, the soft tissue location, and the required strength of the repair. While there exists many techniques to repair soft tissue, there is a growing need to easily and quickly repair a torn meniscus in the knee during arthroscopic surgery.
The meniscus tissue is a fibrocartilaginous structure in the knee joint which performs multiple critical functions, including contributing to normal knee biomechanics and the general well-being of the joint. Generally, the menisci are comprised of two (2) C-shaped fibrocartilaginous structures residing on the tibial plateau. The peripheral rim of a meniscus is thick, tapering to a thin, free inner border. The superior surface is concave to contact the femoral condyles, while the inferior surface is flat to contact the tibial plateau. The fibers forming the menisci are mainly oriented circumferentially throughout the meniscus, parallel to the peripheral border, to withstand hoop stresses placed upon the meniscus by the femoral condyles. It is generally recognized that repair of meniscal lesions, to the extent possible, is preferable to excision so as to attempt to maintain the normality of the meniscus and have it continue to function as intended.
One technique used to repair a torn meniscus is by means of suturing the tear by use of a suture and suture needle. However, a disadvantage with this type of technique is that suturing is relatively time consuming and very labor intensive. Moreover, a great deal of experience is generally required to efficiently repair a torn meniscus using a suture and suture needle. Other techniques involve implanting surgical fasteners using a spring gun. One disadvantage associated with utilizing a surgical fastener is the potential for the surgical fastener to migrate once it has been implanted which could potentially cause patient discomfort. Another disadvantage is directed to the spring gun which generally requires a trigger force that exceeds the spring strength, as well as creates a significant spring recoil once the spring gun is triggered.
What is needed then is a method and apparatus for repairing a torn meniscus which does not suffer from the above-mentioned disadvantages. This, in turn, will reduce the surgical time, complexity and cost, provide a surgical fastener that prohibits migration in the meniscus, provide a portable pneumatic implant device that eliminates spring recoil and reduces trigger resistance while providing sufficient velocity to fully seat the surgical fastener, and provide an implant device that may be readily modified depending on the surgical application and repair required. It is, therefore, an object of the present invention to provide such a method and apparatus for repairing a torn meniscus during an arthroscopic surgical procedure.
In accordance with the teachings of the present invention, a method and apparatus for repairing a torn meniscus during an arthroscopic surgical procedure is disclosed. In this regard, a surgical staple having a pair of legs and a rigid connecting member retaining the legs in a parallel orientation is used to repair the torn meniscus. A portable pneumatic powered implant device is used to easily implant the surgical staple at the desired location during the arthroscopic surgical procedure. The pneumatic powered implant device includes several quick disconnect barrels having different shapes to provide a surgeon with different surgical options.
In one preferred embodiment, a pneumatic powered implant gun drives an implant into a patient. The pneumatic powered implant gun includes a drive shaft, a barrel, a pressurized gas source and a trigger mechanism. The drive shaft is operable to drive the implant into the patient. The barrel slidably receives the drive shaft to guide the implant to a target site. The pressurized gas source is operable to retain pressurized gas. The trigger mechanism releases at least a portion of the pressurized gas to drive the drive shaft along the barrel to drive the implant into the target site.
In another preferred embodiment, a surgical staple for use in repairing tissue in a patient includes a first leg, a second leg and a connection member. The first leg has a first proximal end and a first distal end. The second leg has a second proximal end and a second distal end. The connection member is substantially rigid and operable to substantially retain the first leg relative to the second leg.
In yet another preferred embodiment, a method for driving an implant into a patient is disclosed. This method includes loading an implant within a barrel of pneumatic powered implant gun, engaging the implant with a drive shaft slidably disposed within the barrel, and releasing pressurized gas to drive the drive shaft along the barrel to drive the implant into the patient.
Use of the present invention provides an improved method and apparatus for repairing a torn meniscus during arthroscopic surgical procedures. As a result, the aforementioned disadvantages associated with the currently available methods and techniques for repairing a torn meniscus, as well as other types of soft tissue have been substantially reduced or eliminated.